Question: Does the change in Xenium custom probe panel resuspension buffer or volume impact Xenium performance?
Answer: The change in resuspension buffer and volume for add-on and standalone custom probes does not impact assay performance.
The Xenium add-on and standalone custom gene panel dilution buffer, ‘Xenium Probe Dilution Buffer (PN-2000393), has been discontinued. The Xenium In Situ Gene Expression User Guide (CG000582) has been updated to instruct customers to resuspend the Xenium custom probe panel in TE buffer. We have validated the assay using TE Buffer, TRIS-EDTA, 1X Solution, pH 8.0 Thermo Fisher BP24731 (nuclease-free) (Thermo Fisher Scientific part number AM9624). Any TE, as long as it is the same molecular biology grade, pH, and nuclease-free can be used instead. What alternative TE buffers can be used for Xenium?
In addition to changing the custom probe dilution buffer, the resuspension volume of lyophilized custom probes has been changed. These changes are not associated with the change in dilution buffer (PN-2000393).
There are two different reaction sizes available for add-on and standalone custom probe panels, 4 reaction and 16 reaction kits. The four reaction kit lyophilized oligos are resuspended in 140 ul of TE* pH 8.0; the 16 reaction kit lyophilized oligos are resuspended in 700 ul (previously 625 ul) of TE* pH 8.0.
*If there is sufficient volume of Xenium Probe Dilution Buffer, it may be used interchangeably with TE Buffer. For additional details on custom probe resuspension, please refer to the Xenium In Situ Gene Expression User Guide (CG000582 RevE).
Product: Xenium In Situ Gene Expression